Replacing the control unit (DME) (BMW X5 E53)

Each electronic control unit (ECU) of the KSUD has its own specific program. In each case of ECU replacement, it is necessary to read the software and hardware level using the DIS tester. Depending on the operating mode, the ECU receives various information from the sensors, which is compared with the values stored in its memory. The unit also operates according to a self-learning program, when data on modes and driving styles are accumulated and averaged.

Attention!

• ECU-KSUD may be without power supply (AB is disabled) no more than one hour, otherwise the data on the results of self-training will be lost.
• When installing a new ECU-KSUD (DME), you need to know the number and code of the unit being replaced.

The installation of a new control unit should be carried out only at a service station, since when reinstalling the ECU-KSUD or installing a new unit in the system, it is necessary to enter new data and let the engine run in all its operating modes.

The ECU-KSUD must be removed in the following order. If possible, warm up the engine to operating temperature. Read the readings from the diagnostic loop and record them. Eliminate any detected faults and erase the records from the DME ECU-KSUD fault memory.

If a malfunction is detected due to the ECU-KSUD, then turn off the ignition and connect the DIS-tester or MoDiC. Start work only after turning off the ignition and removing the battery.

Release the retainer and remove the air flow guide of the air conditioner filter. Unscrew the screws (arrow, Fig. 5.185) and remove the cover (1) of the control electronics compartment.

Note: Unscrew the sealing gasket screws (3) only when removing the wiring harness.

Disconnect the ECU-KSUD loops on the DME system unit. Remove the control unit from the clamps, having previously opened them, do not remove the clamps. Remove the ECU-KSUD of the DME system. Further actions with the ECU-KSUD are determined in accordance with the instructions for the DIS tester.

The installation of the ECU-KSUD should be carried out in the reverse order, while it is necessary, when closing the cover of the control electronics compartment, to insert its holders (legs) into the holes and snap the cover into place.

If the control unit has been de-energized for more than one hour or a new unit is being installed, it is necessary to: program the ECU-KSUD; encode ECU-KSUD; read information about faults from the memory of the ECU-KSUD of the "DME" system; troubleshoot and erase fault information from the memory of the memory device; warm up the engine to operating temperature; make a test run of 10-12 km at variable speed, using all possible driving modes. In this case, the control unit will receive all the necessary data for averaging.